Coaxial transmission line



Oct. 3, 1944. Q w, BRUNO 2,359,350

CO-AXIAL TRANSMISSION LINE Filed Aug. 27, 1942 2 Sheets-Sheet 1 IIII'IIII'I'I INVENTOR. Wdham J7 Bmuw ATTORNEY Oct. 3, 1944. w BRUNO (JO-AXIAL TRANSMISSION LINE Filed Aug. 2'7, 1942 I 2 Sheets-Sheet 2 INVENTOR. W/ZZw/m .17. Bran/0 A ORNEY Patented Oct. 3, 1944 COAXIAL TRANSMISSION LINE William A. Bruno, Astoria, Long Island, N. Y., as-

signor to the firm Bruno Patents Inc., Long Island City, N. Y.

Application August 27, 1942, Serial No. 456,317

2 Claims.

This invention relates to transmission lines of co-axial electrical conductors, and has particular relation to joints between sections of co-axial conductors, in which one conductor is concentrically located inside of the other. It is particularly useful for interconnecting sections of ultrahigh frequency co-axial conductors.

The main object of this invention is to provide an improved method and means for properly connecting the tubular outer conductor sections of co-axial transmission lines, as well as the inner conductor sections located inside of said outer conductor sections.

Another object of this invention is to provide a co-axial transmission line which may be of relatively great length, and in which the outer conductor sections and inner conductor sections can be easily assembled in the desired positions.

A further object of the invention is to provide an improved method and means for connecting outer and inner conductors of relatively short conductor sections forming an angle with the main conductor line to the outer and inner con ductors oi. the latter.

Other objects and advantages will appear to those skilled in the art from the following specification an? claims. and the appended drawings which illu trate, by way of example, some pre ferred embodiment -;i ne invention, and in which Figures la and lb res-resent a diagrammatic illustration of a joint formed between two outer conductor sections according t my invention;

Figures 2a, Zb'and 2c llustrate diagrammath cally a T-shaped co-axial conductor line, in which the horizontal conductor comprises sections joined together according to the invention;

Figures 3a, 3b and 3c illustrate a preferred :embiodiment of a T-shaped central conductor oin Figures 4a and 4b illustrate diagrammatically a transmission line comprising several outer conductor sections joined according to this invention, said lines being supported by stubs comprising outer and inner conductors, and

Figures 5a, 5b and 5c show in detail the T- shaped joint 0! the transmission line illustrated in Figs. 4a and 4b, and the cap used therein.

Referring now particularly to Figs. 1a and lb, I and 2 are outer co-axial cable sections having equal, uniform, circular interior cross-sections and being adapted to house co-axially arranged inner conductors (not shown in these figures). In order to connect sections l and 2, a V-shaped incision 3 is made in conductor section I. The

sides 3', 3' of incision 3 form in the drawin s an angle, the vertex of which lies in a central, axial line of cable section I This angle may be a right angle, as shown in the drawings, or an acute or obtuse angle. I prefer the use of an incision corresponding to a right angle. At the end surface of conductor section I, said incision has a width equal to the diameter of the conductor. Conductor section 2 is provided with a V-shaped end registering with V-shaped incision 3, and conductor sections l and 2 may be connected by soldering or welding conductor section I at its V-shaped incision to the V-shaped end of section 2, as shown in Fig. 1b.

In carrying out this invention, a conductor section 2 may be used, which is provided with a V-shaped incision 5. The sides 5, 5' of this incision form in the drawings a right angle, the vertex of which lies in a central, axial line of conductor section 2'. In assembling the transmission line, conductor sections I and 2' may be connected as explained above, and a central conductor is now introduced into the connected outer conducto: section I and 2'. A second central conductor section 6' is now introduced into conductor 2 through incision 5, and connected with central conductor 6 by soldering or welding, as shown in Fig. 2b. Central conductor section 6 is now'introduced into an outer conductor section I, which is provided with a V- shaped end 8, registering with V shaped incision 5, and outer conductor section I is connected by soldering or welding conductor section 2 at its v shaped incision 5 to the V-shaped end of conductor section I, as shown in Fig. 20.

In proceeding in the above described manner, conductor sections I and 2 may be easily and accurately assembled and connected, and yield a smooth, substantially unbroken cylindrical conducting surface. Furthermore, connection of central conductor sections 6 and 6' can be conveniently made through incision 5. The transmission line of the type shown can be easily manufactured and its parts can be assembled to a unit, the parts of which are arranged exactly in their desired position.

Central conductor section 6 and 6' have substantially equal, uniform, circular outside crosssections, and they may be tubular elements or preferably solid rods. In assembling the parts shown in Figs. 2a, 2b and 2c in the above described manner, connection of central conductor sections 6 and 6' may be effected in a manner similar to that above described with reference to outer conductor sections 2' and 1. Thus,

a V-shaped incision 9 is provided in central conductor section 6, the Sides of said incision forming in the drawings a right angle, the vertex of which lies in an axial, central line of conductor section 6. Central conductor section 6' is provided with a V-shaped end 9' registering with incision 9. Conductor section 6 is then soldered or welded at its V-shaped incision 9 to V-shaped end 9 of conductor section 9'.

In the preferred embodiment shown in Figs. 3a3c, a sleeve 3I is slid over central conductor 6. Said sleeve is provided with an orifice 32 and is soldered to conductor 6 at 33 and 33'.

Conductor section 6 has an end portion 34, reglstering with orifice 32, and conductor section 6 may be soldered to sleeve 3| at the periphery of orifice 32. The T-shaped conductor comprising conductor sections 6 and 6' may be assembled with corresponding outer conductor sections substantially 1n the manner explained above in con-' nectioi with 20-20.

The co-axial transmission line shown in Fig ures 4a and 422 comprises several axially aligned outer conductor sections which are connected with each other by soldering at their V-shaped incisions 3 and the adjacent registering V-shaped ends t, according to this invention, A centrally positioned, co-axial inner conductor I6, which consists of a relatively long rod or tube, is housed by outer conductor sections II. The transmission line illustrated in these figures, comprises supporting stubs which consist of outer conductor sections I2, each of which is provided with a cap I4 having as an integral part a central conductor element I5, said elements I5 being provided at their end with a thread I1 and adapted to be screwed into registering elements I8 of central conductor I6. Cap I4 has two edges 4], at which it may be engaged by a tool in order to screw element I5 into part I8.

As shown in Fig. 5a, sleeve3I is slid over central conductor I6, and is soldered to conductor I6 at 33, 33'. Element l8 which is provided with a threaded bore, is soldered to sleeve 3| at the periphery of orifice 32, and is adapted to receive the threaded end portion of central conductor element I5.

In order to assemble the transmission line shown in Fig. 4a, the individual outer conductor sections II are first provided with V-shaped incisions 3 and registerlng V-shaped ends 4, and

also with V-shaped right angle incisions 25. The registering V-shaped ends of outer conductor sections I2 are then connected with individual conductor sections II by soldering at incision 25. Sections II are then connected with each other by soldering, as described above.

Sleeves 3| are slid over central conductor I6, and are soldered to conductor l6 at 33, 33'. Elements I8 are connected to sleeves 3| by soldering. These elements are so dimensioned that assembled rod I6 can be conveniently introduced into the connected outer conductor sections I I.

After introducing central conductor I6 into outer conductor II, caps I4 are applied to outer conductor sections I2 and inner conductor sections I5 are connected with elements I8 by screwing, as shown in Fig. 5a. Finally, caps I4 are connected to conductor sections I2 by soldering at 21.

It will be understood that this invention may be carried out in other specific ways than those herein set forth, and the embodiments should be, therefore, considered as illustrative and not restrictive within the spirit of the invention as defined in the appended claims.

I claim:

1. A co-axial, electrical transmission line comprising a first tubular conductor section provided at its end with a longitudinally arranged V- shaped incision, the sides of which lie in planes, a second tubular conductor section having an inner diameter equal to that of said first section, and a V-shaped end portion registering with said V-shaped incision, said second section being connected to said first section by soldering or welding at said V-shaped incision.

2. A co-axial, electrical transmission line comprising a first tubular outer conductor section provided at its end with a longitudinally arranged V-shaped incision having at the end surface of said section a width equal to the diameter of the section, the sides of said incision lying in planes forming a right angle, the intersection line of said planes lying'in a. central axial plane of the conductor section, a. second tubular outer conductor section'having an inner diameter equal to that of said first section, and a V-shaped end registering with said V-shaped incision, said section being connected to said first section by sol- ,dering or welding at said V-shaped incision.

\ .I A. BRUNO. 

